Adaptations to climate-mediated selective pressures in sheep

Area of Science:

• Animal Genetics
• Climate Adaptation
• Sheep Genomics

Background:

• Sheep (Ovis aries) exhibit remarkable adaptation to varied environments and production systems globally.
• Climate-mediated selective pressures have influenced sheep breed phenotypes and left genetic signatures within their genomes.
• Previous studies primarily used population genetics; this research integrates environmental data with genetic variation.

Purpose of the Study:

• To identify genetic variants in sheep associated with climate-mediated selection.
• To investigate the relationship between single nucleotide polymorphism (SNP) variation and climatic variables.
• To explore candidate genes involved in adaptation to local climates.

Main Methods:

• Analyzed 49,034 SNPs across 32 autochthonous sheep breeds.
• Integrated environmental data with SNP variation for coanalysis.
• Performed gene ontology analysis and examined linkage disequilibrium and haplotype homozygosity.

Main Results:

• Identified 230 SNPs potentially linked to climate-mediated selection.
• Found significant correlations between allele frequencies and climatic variables for 189 SNPs (82%).
• Identified candidate genes related to GTPase regulator and peptide receptor activities, impacting energy metabolism and regulation.

Conclusions:

• Climate adaptation has shaped the spatial distribution of specific genetic variants in sheep.
• Identified core haplotypes and alleles with geographic patterns correlating with climate.
• These findings provide insights into the genetic basis of sheep adaptation to diverse climates.